1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_CODE_NMETHOD_HPP
26 #define SHARE_CODE_NMETHOD_HPP
27
28 #include "code/codeBlob.hpp"
29 #include "code/pcDesc.hpp"
30 #include "oops/metadata.hpp"
31 #include "oops/method.hpp"
32
33 class AbstractCompiler;
34 class CompiledDirectCall;
35 class CompiledIC;
36 class CompiledICData;
37 class CompileTask;
38 class DepChange;
39 class Dependencies;
40 class DirectiveSet;
41 class DebugInformationRecorder;
42 class ExceptionHandlerTable;
43 class ImplicitExceptionTable;
44 class JvmtiThreadState;
45 class MetadataClosure;
46 class NativeCallWrapper;
47 class OopIterateClosure;
48 class AOTCodeReader;
49 class AOTCodeEntry;
50 class ScopeDesc;
51 class xmlStream;
52
53 // This class is used internally by nmethods, to cache
54 // exception/pc/handler information.
55
56 class ExceptionCache : public CHeapObj<mtCode> {
57 friend class VMStructs;
58 private:
59 enum { cache_size = 16 };
60 Klass* _exception_type;
61 address _pc[cache_size];
62 address _handler[cache_size];
63 volatile int _count;
64 ExceptionCache* volatile _next;
65 ExceptionCache* _purge_list_next;
66
67 inline address pc_at(int index);
68 void set_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; }
69
70 inline address handler_at(int index);
71 void set_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; }
72
73 inline int count();
74 // increment_count is only called under lock, but there may be concurrent readers.
75 void increment_count();
76
77 public:
78
79 ExceptionCache(Handle exception, address pc, address handler);
80
81 Klass* exception_type() { return _exception_type; }
82 ExceptionCache* next();
83 void set_next(ExceptionCache *ec);
84 ExceptionCache* purge_list_next() { return _purge_list_next; }
85 void set_purge_list_next(ExceptionCache *ec) { _purge_list_next = ec; }
86
87 address match(Handle exception, address pc);
88 bool match_exception_with_space(Handle exception) ;
89 address test_address(address addr);
90 bool add_address_and_handler(address addr, address handler) ;
91 };
92
93 // cache pc descs found in earlier inquiries
94 class PcDescCache {
95 friend class VMStructs;
96 private:
97 enum { cache_size = 4 };
98 // The array elements MUST be volatile! Several threads may modify
99 // and read from the cache concurrently. find_pc_desc_internal has
100 // returned wrong results. C++ compiler (namely xlC12) may duplicate
101 // C++ field accesses if the elements are not volatile.
102 typedef PcDesc* PcDescPtr;
103 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
104 public:
105 PcDescCache() { DEBUG_ONLY(_pc_descs[0] = nullptr); }
106 void init_to(PcDesc* initial_pc_desc);
107 PcDesc* find_pc_desc(int pc_offset, bool approximate);
108 void add_pc_desc(PcDesc* pc_desc);
109 PcDesc* last_pc_desc() { return _pc_descs[0]; }
110 };
111
112 class PcDescContainer : public CHeapObj<mtCode> {
113 private:
114 PcDescCache _pc_desc_cache;
115 public:
116 PcDescContainer(PcDesc* initial_pc_desc) { _pc_desc_cache.init_to(initial_pc_desc); }
117
118 PcDesc* find_pc_desc_internal(address pc, bool approximate, address code_begin,
119 PcDesc* lower, PcDesc* upper);
120
121 PcDesc* find_pc_desc(address pc, bool approximate, address code_begin, PcDesc* lower, PcDesc* upper)
122 #ifdef PRODUCT
123 {
124 PcDesc* desc = _pc_desc_cache.last_pc_desc();
125 assert(desc != nullptr, "PcDesc cache should be initialized already");
126 if (desc->pc_offset() == (pc - code_begin)) {
127 // Cached value matched
128 return desc;
129 }
130 return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
131 }
132 #endif
133 ;
134 };
135
136 // nmethods (native methods) are the compiled code versions of Java methods.
137 //
138 // An nmethod contains:
139 // - Header (the nmethod structure)
140 // - Constant part (doubles, longs and floats used in nmethod)
141 // - Code part:
142 // - Code body
143 // - Exception handler
144 // - Stub code
145 // - OOP table
146 //
147 // As a CodeBlob, an nmethod references [mutable data] allocated on the C heap:
148 // - CodeBlob relocation data
149 // - Metainfo
150 // - JVMCI data
151 //
152 // An nmethod references [immutable data] allocated on C heap:
153 // - Dependency assertions data
154 // - Implicit null table array
155 // - Handler entry point array
156 // - Debugging information:
157 // - Scopes data array
158 // - Scopes pcs array
159 // - JVMCI speculations array
160
161 #if INCLUDE_JVMCI
162 class FailedSpeculation;
163 class JVMCINMethodData;
164 #endif
165
166 class nmethod : public CodeBlob {
167 friend class VMStructs;
168 friend class JVMCIVMStructs;
169 friend class CodeCache; // scavengable oops
170 friend class JVMCINMethodData;
171 friend class DeoptimizationScope;
172
173 private:
174
175 // Used to track in which deoptimize handshake this method will be deoptimized.
176 uint64_t _deoptimization_generation;
177
178 uint64_t _gc_epoch;
179
180 // Profiling counter used to figure out the hottest nmethods to record into CDS
181 volatile uint64_t _method_profiling_count;
182
183 Method* _method;
184
185 // To reduce header size union fields which usages do not overlap.
186 union {
187 // To support simple linked-list chaining of nmethods:
188 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
189 struct {
190 // These are used for compiled synchronized native methods to
191 // locate the owner and stack slot for the BasicLock. They are
192 // needed because there is no debug information for compiled native
193 // wrappers and the oop maps are insufficient to allow
194 // frame::retrieve_receiver() to work. Currently they are expected
195 // to be byte offsets from the Java stack pointer for maximum code
196 // sharing between platforms. JVMTI's GetLocalInstance() uses these
197 // offsets to find the receiver for non-static native wrapper frames.
198 ByteSize _native_receiver_sp_offset;
199 ByteSize _native_basic_lock_sp_offset;
200 };
201 };
202
203 // nmethod's read-only data
204 address _immutable_data;
205
206 PcDescContainer* _pc_desc_container;
207 ExceptionCache* volatile _exception_cache;
208
209 void* _gc_data;
210
211 struct oops_do_mark_link; // Opaque data type.
212 static nmethod* volatile _oops_do_mark_nmethods;
213 oops_do_mark_link* volatile _oops_do_mark_link;
214
215 CompiledICData* _compiled_ic_data;
216
217 // offsets for entry points
218 address _osr_entry_point; // entry point for on stack replacement
219 uint16_t _entry_offset; // entry point with class check
220 uint16_t _verified_entry_offset; // entry point without class check
221 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
222 int _immutable_data_size;
223
224 // _consts_offset == _content_offset because SECT_CONSTS is first in code buffer
225
226 int _skipped_instructions_size;
227
228 int _stub_offset;
229
230 // Offsets for different stubs section parts
231 int _exception_offset;
232 // All deoptee's will resume execution at this location described by
233 // this offset.
234 int _deopt_handler_offset;
235 // All deoptee's at a MethodHandle call site will resume execution
236 // at this location described by this offset.
237 int _deopt_mh_handler_offset;
238 // Offset (from insts_end) of the unwind handler if it exists
239 int16_t _unwind_handler_offset;
240 // Number of arguments passed on the stack
241 uint16_t _num_stack_arg_slots;
242
243 uint16_t _oops_size;
244 #if INCLUDE_JVMCI
245 // _metadata_size is not specific to JVMCI. In the non-JVMCI case, it can be derived as:
246 // _metadata_size = mutable_data_size - relocation_size
247 uint16_t _metadata_size;
248 #endif
249
250 // Offset in immutable data section
251 // _dependencies_offset == 0
252 uint16_t _nul_chk_table_offset;
253 uint16_t _handler_table_offset; // This table could be big in C1 code
254 int _scopes_pcs_offset;
255 int _scopes_data_offset;
256 #if INCLUDE_JVMCI
257 int _speculations_offset;
258 #endif
259
260 // location in frame (offset for sp) that deopt can store the original
261 // pc during a deopt.
262 int _orig_pc_offset;
263
264 int _compile_id; // which compilation made this nmethod
265 CompLevel _comp_level; // compilation level (s1)
266 CompilerType _compiler_type; // which compiler made this nmethod (u1)
267
268 AOTCodeEntry* _aot_code_entry;
269
270 bool _used; // has this nmethod ever been invoked?
271
272 // Local state used to keep track of whether unloading is happening or not
273 volatile uint8_t _is_unloading_state;
274
275 // Protected by NMethodState_lock
276 volatile signed char _state; // {not_installed, in_use, not_entrant}
277
278 // set during construction
279 uint8_t _has_unsafe_access:1, // May fault due to unsafe access.
280 _has_method_handle_invokes:1,// Has this method MethodHandle invokes?
281 _has_wide_vectors:1, // Preserve wide vectors at safepoints
282 _has_monitors:1, // Fastpath monitor detection for continuations
283 _has_scoped_access:1, // used by for shared scope closure (scopedMemoryAccess.cpp)
284 _has_flushed_dependencies:1, // Used for maintenance of dependencies (under CodeCache_lock)
285 _is_unlinked:1, // mark during class unloading
286 _load_reported:1, // used by jvmti to track if an event has been posted for this nmethod
287 _preloaded:1,
288 _has_clinit_barriers:1;
289
290 enum DeoptimizationStatus : u1 {
291 not_marked,
292 deoptimize,
293 deoptimize_noupdate,
294 deoptimize_done
295 };
296
297 volatile DeoptimizationStatus _deoptimization_status; // Used for stack deoptimization
298
299 DeoptimizationStatus deoptimization_status() const {
300 return Atomic::load(&_deoptimization_status);
301 }
302
303 // Initialize fields to their default values
304 void init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets);
305
306 // Post initialization
307 void post_init();
308
309 // For native wrappers
310 nmethod(Method* method,
311 CompilerType type,
312 int nmethod_size,
313 int compile_id,
314 CodeOffsets* offsets,
315 CodeBuffer *code_buffer,
316 int frame_size,
317 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
318 ByteSize basic_lock_sp_offset, /* synchronized natives only */
319 OopMapSet* oop_maps,
320 int mutable_data_size);
321
322 // For normal JIT compiled code
323 nmethod(Method* method,
324 CompilerType type,
325 int nmethod_size,
326 int immutable_data_size,
327 int mutable_data_size,
328 int compile_id,
329 int entry_bci,
330 address immutable_data,
331 CodeOffsets* offsets,
332 int orig_pc_offset,
333 DebugInformationRecorder *recorder,
334 Dependencies* dependencies,
335 CodeBuffer *code_buffer,
336 int frame_size,
337 OopMapSet* oop_maps,
338 ExceptionHandlerTable* handler_table,
339 ImplicitExceptionTable* nul_chk_table,
340 AbstractCompiler* compiler,
341 CompLevel comp_level
342 , AOTCodeEntry* aot_code_entry
343 #if INCLUDE_JVMCI
344 , char* speculations = nullptr,
345 int speculations_len = 0,
346 JVMCINMethodData* jvmci_data = nullptr
347 #endif
348 );
349
350 // helper methods
351 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
352
353 // For method handle intrinsics: Try MethodNonProfiled, MethodProfiled and NonNMethod.
354 // Attention: Only allow NonNMethod space for special nmethods which don't need to be
355 // findable by nmethod iterators! In particular, they must not contain oops!
356 void* operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw();
357
358 const char* reloc_string_for(u_char* begin, u_char* end);
359
360 bool try_transition(signed char new_state);
361
362 // Returns true if this thread changed the state of the nmethod or
363 // false if another thread performed the transition.
364 bool make_entrant() { Unimplemented(); return false; }
365 void inc_decompile_count();
366
367 // Inform external interfaces that a compiled method has been unloaded
368 void post_compiled_method_unload();
369
370 PcDesc* find_pc_desc(address pc, bool approximate) {
371 if (_pc_desc_container == nullptr) return nullptr; // native method
372 return _pc_desc_container->find_pc_desc(pc, approximate, code_begin(), scopes_pcs_begin(), scopes_pcs_end());
373 }
374
375 // STW two-phase nmethod root processing helpers.
376 //
377 // When determining liveness of a given nmethod to do code cache unloading,
378 // some collectors need to do different things depending on whether the nmethods
379 // need to absolutely be kept alive during root processing; "strong"ly reachable
380 // nmethods are known to be kept alive at root processing, but the liveness of
381 // "weak"ly reachable ones is to be determined later.
382 //
383 // We want to allow strong and weak processing of nmethods by different threads
384 // at the same time without heavy synchronization. Additional constraints are
385 // to make sure that every nmethod is processed a minimal amount of time, and
386 // nmethods themselves are always iterated at most once at a particular time.
387 //
388 // Note that strong processing work must be a superset of weak processing work
389 // for this code to work.
390 //
391 // We store state and claim information in the _oops_do_mark_link member, using
392 // the two LSBs for the state and the remaining upper bits for linking together
393 // nmethods that were already visited.
394 // The last element is self-looped, i.e. points to itself to avoid some special
395 // "end-of-list" sentinel value.
396 //
397 // _oops_do_mark_link special values:
398 //
399 // _oops_do_mark_link == nullptr: the nmethod has not been visited at all yet, i.e.
400 // is Unclaimed.
401 //
402 // For other values, its lowest two bits indicate the following states of the nmethod:
403 //
404 // weak_request (WR): the nmethod has been claimed by a thread for weak processing
405 // weak_done (WD): weak processing has been completed for this nmethod.
406 // strong_request (SR): the nmethod has been found to need strong processing while
407 // being weak processed.
408 // strong_done (SD): strong processing has been completed for this nmethod .
409 //
410 // The following shows the _only_ possible progressions of the _oops_do_mark_link
411 // pointer.
412 //
413 // Given
414 // N as the nmethod
415 // X the current next value of _oops_do_mark_link
416 //
417 // Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
418 // a single thread.
419 // Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
420 // completed (as above) another thread found that the nmethod needs strong
421 // processing after all.
422 // Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
423 // thread finds that the nmethod needs strong processing, marks it as such and
424 // terminates. The original thread completes strong processing.
425 // Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
426 // the beginning by a single thread.
427 //
428 // "|" describes the concatenation of bits in _oops_do_mark_link.
429 //
430 // The diagram also describes the threads responsible for changing the nmethod to
431 // the next state by marking the _transition_ with (C) and (O), which mean "current"
432 // and "other" thread respectively.
433 //
434
435 // States used for claiming nmethods during root processing.
436 static const uint claim_weak_request_tag = 0;
437 static const uint claim_weak_done_tag = 1;
438 static const uint claim_strong_request_tag = 2;
439 static const uint claim_strong_done_tag = 3;
440
441 static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
442 assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
443 assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
444 return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
445 }
446
447 static uint extract_state(oops_do_mark_link* link) {
448 return (uint)((uintptr_t)link & 0x3);
449 }
450
451 static nmethod* extract_nmethod(oops_do_mark_link* link) {
452 return (nmethod*)((uintptr_t)link & ~0x3);
453 }
454
455 void oops_do_log_change(const char* state);
456
457 static bool oops_do_has_weak_request(oops_do_mark_link* next) {
458 return extract_state(next) == claim_weak_request_tag;
459 }
460
461 static bool oops_do_has_any_strong_state(oops_do_mark_link* next) {
462 return extract_state(next) >= claim_strong_request_tag;
463 }
464
465 // Attempt Unclaimed -> N|WR transition. Returns true if successful.
466 bool oops_do_try_claim_weak_request();
467
468 // Attempt Unclaimed -> N|SD transition. Returns the current link.
469 oops_do_mark_link* oops_do_try_claim_strong_done();
470 // Attempt N|WR -> X|WD transition. Returns nullptr if successful, X otherwise.
471 nmethod* oops_do_try_add_to_list_as_weak_done();
472
473 // Attempt X|WD -> N|SR transition. Returns the current link.
474 oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
475 // Attempt X|WD -> X|SD transition. Returns true if successful.
476 bool oops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);
477
478 // Do the N|SD -> X|SD transition.
479 void oops_do_add_to_list_as_strong_done();
480
481 // Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
482 // transitions).
483 void oops_do_set_strong_done(nmethod* old_head);
484
485 void record_nmethod_dependency();
486
487 nmethod* restore(address code_cache_buffer,
488 const methodHandle& method,
489 int compile_id,
490 address reloc_data,
491 GrowableArray<Handle>& oop_list,
492 GrowableArray<Metadata*>& metadata_list,
493 ImmutableOopMapSet* oop_maps,
494 address immutable_data,
495 GrowableArray<Handle>& reloc_imm_oop_list,
496 GrowableArray<Metadata*>& reloc_imm_metadata_list,
497 AOTCodeReader* aot_code_reader);
498
499 public:
500 // create nmethod using archived nmethod from AOT code cache
501 static nmethod* new_nmethod(nmethod* archived_nm,
502 const methodHandle& method,
503 AbstractCompiler* compiler,
504 int compile_id,
505 address reloc_data,
506 GrowableArray<Handle>& oop_list,
507 GrowableArray<Metadata*>& metadata_list,
508 ImmutableOopMapSet* oop_maps,
509 address immutable_data,
510 GrowableArray<Handle>& reloc_imm_oop_list,
511 GrowableArray<Metadata*>& reloc_imm_metadata_list,
512 AOTCodeReader* aot_code_reader);
513
514 // create nmethod with entry_bci
515 static nmethod* new_nmethod(const methodHandle& method,
516 int compile_id,
517 int entry_bci,
518 CodeOffsets* offsets,
519 int orig_pc_offset,
520 DebugInformationRecorder* recorder,
521 Dependencies* dependencies,
522 CodeBuffer *code_buffer,
523 int frame_size,
524 OopMapSet* oop_maps,
525 ExceptionHandlerTable* handler_table,
526 ImplicitExceptionTable* nul_chk_table,
527 AbstractCompiler* compiler,
528 CompLevel comp_level
529 , AOTCodeEntry* aot_code_entry
530 #if INCLUDE_JVMCI
531 , char* speculations = nullptr,
532 int speculations_len = 0,
533 JVMCINMethodData* jvmci_data = nullptr
534 #endif
535 );
536
537 static nmethod* new_native_nmethod(const methodHandle& method,
538 int compile_id,
539 CodeBuffer *code_buffer,
540 int vep_offset,
541 int frame_complete,
542 int frame_size,
543 ByteSize receiver_sp_offset,
544 ByteSize basic_lock_sp_offset,
545 OopMapSet* oop_maps,
546 int exception_handler = -1);
547
548 Method* method () const { return _method; }
549 uint16_t entry_bci () const { return _entry_bci; }
550 bool is_native_method() const { return _method != nullptr && _method->is_native(); }
551 bool is_java_method () const { return _method != nullptr && !_method->is_native(); }
552 bool is_osr_method () const { return _entry_bci != InvocationEntryBci; }
553
554 // Compiler task identification. Note that all OSR methods
555 // are numbered in an independent sequence if CICountOSR is true,
556 // and native method wrappers are also numbered independently if
557 // CICountNative is true.
558 int compile_id() const { return _compile_id; }
559 const char* compile_kind() const;
560
561 inline bool is_compiled_by_c1 () const { return _compiler_type == compiler_c1; }
562 inline bool is_compiled_by_c2 () const { return _compiler_type == compiler_c2; }
563 inline bool is_compiled_by_jvmci() const { return _compiler_type == compiler_jvmci; }
564 CompilerType compiler_type () const { return _compiler_type; }
565 const char* compiler_name () const;
566
567 // boundaries for different parts
568 address consts_begin () const { return content_begin(); }
569 address consts_end () const { return code_begin() ; }
570 address insts_begin () const { return code_begin() ; }
571 address insts_end () const { return header_begin() + _stub_offset ; }
572 address stub_begin () const { return header_begin() + _stub_offset ; }
573 address stub_end () const { return code_end() ; }
574 address exception_begin () const { return header_begin() + _exception_offset ; }
575 address deopt_handler_begin () const { return header_begin() + _deopt_handler_offset ; }
576 address deopt_mh_handler_begin() const { return _deopt_mh_handler_offset != -1 ? (header_begin() + _deopt_mh_handler_offset) : nullptr; }
577 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (insts_end() - _unwind_handler_offset) : nullptr; }
578 oop* oops_begin () const { return (oop*) data_begin(); }
579 oop* oops_end () const { return (oop*) data_end(); }
580
581 // mutable data
582 Metadata** metadata_begin () const { return (Metadata**) (mutable_data_begin() + _relocation_size); }
583 #if INCLUDE_JVMCI
584 Metadata** metadata_end () const { return (Metadata**) (mutable_data_begin() + _relocation_size + _metadata_size); }
585 address jvmci_data_begin () const { return mutable_data_begin() + _relocation_size + _metadata_size; }
586 address jvmci_data_end () const { return mutable_data_end(); }
587 #else
588 Metadata** metadata_end () const { return (Metadata**) mutable_data_end(); }
589 #endif
590
591 // immutable data
592 void set_immutable_data(address data) { _immutable_data = data; }
593 address immutable_data_begin () const { return _immutable_data; }
594 address immutable_data_end () const { return _immutable_data + _immutable_data_size ; }
595 address dependencies_begin () const { return _immutable_data; }
596 address dependencies_end () const { return _immutable_data + _nul_chk_table_offset; }
597 address nul_chk_table_begin () const { return _immutable_data + _nul_chk_table_offset; }
598 address nul_chk_table_end () const { return _immutable_data + _handler_table_offset; }
599 address handler_table_begin () const { return _immutable_data + _handler_table_offset; }
600 address handler_table_end () const { return _immutable_data + _scopes_pcs_offset ; }
601 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(_immutable_data + _scopes_pcs_offset) ; }
602 PcDesc* scopes_pcs_end () const { return (PcDesc*)(_immutable_data + _scopes_data_offset) ; }
603 address scopes_data_begin () const { return _immutable_data + _scopes_data_offset ; }
604
605 #if INCLUDE_JVMCI
606 address scopes_data_end () const { return _immutable_data + _speculations_offset ; }
607 address speculations_begin () const { return _immutable_data + _speculations_offset ; }
608 address speculations_end () const { return immutable_data_end(); }
609 #else
610 address scopes_data_end () const { return immutable_data_end(); }
611 #endif
612
613 // Sizes
614 int immutable_data_size() const { return _immutable_data_size; }
615 int consts_size () const { return int( consts_end () - consts_begin ()); }
616 int insts_size () const { return int( insts_end () - insts_begin ()); }
617 int stub_size () const { return int( stub_end () - stub_begin ()); }
618 int oops_size () const { return int((address) oops_end () - (address) oops_begin ()); }
619 int metadata_size () const { return int((address) metadata_end () - (address) metadata_begin ()); }
620 int scopes_data_size () const { return int( scopes_data_end () - scopes_data_begin ()); }
621 int scopes_pcs_size () const { return int((intptr_t)scopes_pcs_end () - (intptr_t)scopes_pcs_begin ()); }
622 int dependencies_size () const { return int( dependencies_end () - dependencies_begin ()); }
623 int handler_table_size () const { return int( handler_table_end() - handler_table_begin()); }
624 int nul_chk_table_size () const { return int( nul_chk_table_end() - nul_chk_table_begin()); }
625 #if INCLUDE_JVMCI
626 int speculations_size () const { return int( speculations_end () - speculations_begin ()); }
627 int jvmci_data_size () const { return int( jvmci_data_end () - jvmci_data_begin ()); }
628 #endif
629
630 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
631 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
632
633 int skipped_instructions_size () const { return _skipped_instructions_size; }
634 int total_size() const;
635
636 // Containment
637 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); }
638 // Returns true if a given address is in the 'insts' section. The method
639 // insts_contains_inclusive() is end-inclusive.
640 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); }
641 bool insts_contains_inclusive(address addr) const { return insts_begin () <= addr && addr <= insts_end (); }
642 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); }
643 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
644 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
645 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
646 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
647 bool handler_table_contains (address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); }
648 bool nul_chk_table_contains (address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }
649
650 // entry points
651 address entry_point() const { return code_begin() + _entry_offset; } // normal entry point
652 address verified_entry_point() const { return code_begin() + _verified_entry_offset; } // if klass is correct
653
654 enum : signed char { not_installed = -1, // in construction, only the owner doing the construction is
655 // allowed to advance state
656 in_use = 0, // executable nmethod
657 not_entrant = 1 // marked for deoptimization but activations may still exist
658 };
659
660 // flag accessing and manipulation
661 bool is_not_installed() const { return _state == not_installed; }
662 bool is_in_use() const { return _state <= in_use; }
663 bool is_not_entrant() const { return _state == not_entrant; }
664 int get_state() const { return _state; }
665
666 void clear_unloading_state();
667 // Heuristically deduce an nmethod isn't worth keeping around
668 bool is_cold();
669 bool is_unloading();
670 void do_unloading(bool unloading_occurred);
671
672 void inc_method_profiling_count();
673 uint64_t method_profiling_count();
674
675 bool make_in_use() {
676 return try_transition(in_use);
677 }
678 // Make the nmethod non entrant. The nmethod will continue to be
679 // alive. It is used when an uncommon trap happens. Returns true
680 // if this thread changed the state of the nmethod or false if
681 // another thread performed the transition.
682 bool make_not_entrant(const char* reason, bool make_not_entrant = true);
683 bool make_not_used() { return make_not_entrant("not used"); }
684
685 bool is_marked_for_deoptimization() const { return deoptimization_status() != not_marked; }
686 bool has_been_deoptimized() const { return deoptimization_status() == deoptimize_done; }
687 void set_deoptimized_done();
688
689 bool update_recompile_counts() const {
690 // Update recompile counts when either the update is explicitly requested (deoptimize)
691 // or the nmethod is not marked for deoptimization at all (not_marked).
692 // The latter happens during uncommon traps when deoptimized nmethod is made not entrant.
693 DeoptimizationStatus status = deoptimization_status();
694 return status != deoptimize_noupdate && status != deoptimize_done;
695 }
696
697 // tells whether frames described by this nmethod can be deoptimized
698 // note: native wrappers cannot be deoptimized.
699 bool can_be_deoptimized() const { return is_java_method(); }
700
701 bool has_dependencies() { return dependencies_size() != 0; }
702 void print_dependencies_on(outputStream* out) PRODUCT_RETURN;
703 void flush_dependencies();
704
705 template<typename T>
706 T* gc_data() const { return reinterpret_cast<T*>(_gc_data); }
707 template<typename T>
708 void set_gc_data(T* gc_data) { _gc_data = reinterpret_cast<void*>(gc_data); }
709
710 bool has_unsafe_access() const { return _has_unsafe_access; }
711 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; }
712
713 bool has_monitors() const { return _has_monitors; }
714 void set_has_monitors(bool z) { _has_monitors = z; }
715
716 bool has_scoped_access() const { return _has_scoped_access; }
717 void set_has_scoped_access(bool z) { _has_scoped_access = z; }
718
719 bool has_method_handle_invokes() const { return _has_method_handle_invokes; }
720 void set_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; }
721
722 bool has_wide_vectors() const { return _has_wide_vectors; }
723 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; }
724
725 bool has_clinit_barriers() const { return _has_clinit_barriers; }
726 void set_has_clinit_barriers(bool z) { _has_clinit_barriers = z; }
727
728 bool preloaded() const { return _preloaded; }
729 void set_preloaded(bool z) { _preloaded = z; }
730
731 bool has_flushed_dependencies() const { return _has_flushed_dependencies; }
732 void set_has_flushed_dependencies(bool z) {
733 assert(!has_flushed_dependencies(), "should only happen once");
734 _has_flushed_dependencies = z;
735 }
736
737 bool is_unlinked() const { return _is_unlinked; }
738 void set_is_unlinked() {
739 assert(!_is_unlinked, "already unlinked");
740 _is_unlinked = true;
741 }
742
743 int comp_level() const { return _comp_level; }
744
745 // Support for oops in scopes and relocs:
746 // Note: index 0 is reserved for null.
747 oop oop_at(int index) const;
748 oop oop_at_phantom(int index) const; // phantom reference
749 oop* oop_addr_at(int index) const { // for GC
750 // relocation indexes are biased by 1 (because 0 is reserved)
751 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
752 return &oops_begin()[index - 1];
753 }
754
755 // Support for meta data in scopes and relocs:
756 // Note: index 0 is reserved for null.
757 Metadata* metadata_at(int index) const { return index == 0 ? nullptr: *metadata_addr_at(index); }
758 Metadata** metadata_addr_at(int index) const { // for GC
759 // relocation indexes are biased by 1 (because 0 is reserved)
760 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
761 return &metadata_begin()[index - 1];
762 }
763
764 void copy_values(GrowableArray<Handle>* array);
765 void copy_values(GrowableArray<jobject>* oops);
766 void copy_values(GrowableArray<Metadata*>* metadata);
767 void copy_values(GrowableArray<address>* metadata) {} // Nothing to do
768
769 // Relocation support
770 private:
771 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
772 inline void initialize_immediate_oop(oop* dest, jobject handle);
773
774 protected:
775 address oops_reloc_begin() const;
776
777 public:
778 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
779 void fix_oop_relocations() { fix_oop_relocations(nullptr, nullptr, false); }
780
781 void create_reloc_immediates_list(JavaThread* thread, GrowableArray<Handle>& oop_list, GrowableArray<Metadata*>& metadata_list);
782
783 bool is_at_poll_return(address pc);
784 bool is_at_poll_or_poll_return(address pc);
785
786 protected:
787 // Exception cache support
788 // Note: _exception_cache may be read and cleaned concurrently.
789 ExceptionCache* exception_cache() const { return _exception_cache; }
790 ExceptionCache* exception_cache_acquire() const;
791
792 public:
793 address handler_for_exception_and_pc(Handle exception, address pc);
794 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler);
795 void clean_exception_cache();
796
797 void add_exception_cache_entry(ExceptionCache* new_entry);
798 ExceptionCache* exception_cache_entry_for_exception(Handle exception);
799
800
801 // MethodHandle
802 bool is_method_handle_return(address return_pc);
803 // Deopt
804 // Return true is the PC is one would expect if the frame is being deopted.
805 inline bool is_deopt_pc(address pc);
806 inline bool is_deopt_mh_entry(address pc);
807 inline bool is_deopt_entry(address pc);
808
809 // Accessor/mutator for the original pc of a frame before a frame was deopted.
810 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
811 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
812
813 const char* state() const;
814
815 bool inlinecache_check_contains(address addr) const {
816 return (addr >= code_begin() && addr < verified_entry_point());
817 }
818
819 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f);
820
821 // implicit exceptions support
822 address continuation_for_implicit_div0_exception(address pc) { return continuation_for_implicit_exception(pc, true); }
823 address continuation_for_implicit_null_exception(address pc) { return continuation_for_implicit_exception(pc, false); }
824
825 // Inline cache support for class unloading and nmethod unloading
826 private:
827 void cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all);
828
829 address continuation_for_implicit_exception(address pc, bool for_div0_check);
830
831 public:
832 // Serial version used by whitebox test
833 void cleanup_inline_caches_whitebox();
834
835 void clear_inline_caches();
836
837 // Execute nmethod barrier code, as if entering through nmethod call.
838 void run_nmethod_entry_barrier();
839
840 void verify_oop_relocations();
841
842 bool has_evol_metadata();
843
844 Method* attached_method(address call_pc);
845 Method* attached_method_before_pc(address pc);
846
847 // GC unloading support
848 // Cleans unloaded klasses and unloaded nmethods in inline caches
849
850 void unload_nmethod_caches(bool class_unloading_occurred);
851
852 void unlink_from_method();
853
854 // On-stack replacement support
855 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
856 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
857 nmethod* osr_link() const { return _osr_link; }
858 void set_osr_link(nmethod *n) { _osr_link = n; }
859 void invalidate_osr_method();
860
861 int num_stack_arg_slots(bool rounded = true) const {
862 return rounded ? align_up(_num_stack_arg_slots, 2) : _num_stack_arg_slots;
863 }
864
865 // Verify calls to dead methods have been cleaned.
866 void verify_clean_inline_caches();
867
868 // Unlink this nmethod from the system
869 void unlink();
870
871 // Deallocate this nmethod - called by the GC
872 void purge(bool unregister_nmethod);
873
874 // See comment at definition of _last_seen_on_stack
875 void mark_as_maybe_on_stack();
876 bool is_maybe_on_stack();
877
878 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
879 void set_method(Method* method) { _method = method; }
880
881 #if INCLUDE_JVMCI
882 // Gets the JVMCI name of this nmethod.
883 const char* jvmci_name();
884
885 // Records the pending failed speculation in the
886 // JVMCI speculation log associated with this nmethod.
887 void update_speculation(JavaThread* thread);
888
889 // Gets the data specific to a JVMCI compiled method.
890 // This returns a non-nullptr value iff this nmethod was
891 // compiled by the JVMCI compiler.
892 JVMCINMethodData* jvmci_nmethod_data() const {
893 return jvmci_data_size() == 0 ? nullptr : (JVMCINMethodData*) jvmci_data_begin();
894 }
895 #endif
896
897 void oops_do(OopClosure* f) { oops_do(f, false); }
898 void oops_do(OopClosure* f, bool allow_dead);
899
900 // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
901 // nmethod.
902 bool oops_do_try_claim();
903
904 // Loom support for following nmethods on the stack
905 void follow_nmethod(OopIterateClosure* cl);
906
907 // Class containing callbacks for the oops_do_process_weak/strong() methods
908 // below.
909 class OopsDoProcessor {
910 public:
911 // Process the oops of the given nmethod based on whether it has been called
912 // in a weak or strong processing context, i.e. apply either weak or strong
913 // work on it.
914 virtual void do_regular_processing(nmethod* nm) = 0;
915 // Assuming that the oops of the given nmethod has already been its weak
916 // processing applied, apply the remaining strong processing part.
917 virtual void do_remaining_strong_processing(nmethod* nm) = 0;
918 };
919
920 // The following two methods do the work corresponding to weak/strong nmethod
921 // processing.
922 void oops_do_process_weak(OopsDoProcessor* p);
923 void oops_do_process_strong(OopsDoProcessor* p);
924
925 static void oops_do_marking_prologue();
926 static void oops_do_marking_epilogue();
927
928 private:
929 ScopeDesc* scope_desc_in(address begin, address end);
930
931 address* orig_pc_addr(const frame* fr);
932
933 // used by jvmti to track if the load events has been reported
934 bool load_reported() const { return _load_reported; }
935 void set_load_reported() { _load_reported = true; }
936
937 public:
938 // ScopeDesc retrieval operation
939 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); }
940 // pc_desc_near returns the first PcDesc at or after the given pc.
941 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); }
942
943 // ScopeDesc for an instruction
944 ScopeDesc* scope_desc_at(address pc);
945 ScopeDesc* scope_desc_near(address pc);
946
947 // copying of debugging information
948 void copy_scopes_pcs(PcDesc* pcs, int count);
949 void copy_scopes_data(address buffer, int size);
950
951 int orig_pc_offset() { return _orig_pc_offset; }
952
953 AOTCodeEntry* aot_code_entry() const { return _aot_code_entry; }
954 bool is_aot() const { return aot_code_entry() != nullptr; }
955 void set_aot_code_entry(AOTCodeEntry* entry) { _aot_code_entry = entry; }
956
957 bool used() const { return _used; }
958 void set_used() { _used = true; }
959
960 // Post successful compilation
961 void post_compiled_method(CompileTask* task);
962
963 // jvmti support:
964 void post_compiled_method_load_event(JvmtiThreadState* state = nullptr);
965
966 // verify operations
967 void verify();
968 void verify_scopes();
969 void verify_interrupt_point(address interrupt_point, bool is_inline_cache);
970
971 // Disassemble this nmethod with additional debug information, e.g. information about blocks.
972 void decode2(outputStream* st) const;
973 void print_constant_pool(outputStream* st);
974
975 // Avoid hiding of parent's 'decode(outputStream*)' method.
976 void decode(outputStream* st) const { decode2(st); } // just delegate here.
977
978 // printing support
979 void print_on_impl(outputStream* st) const;
980 void print_code();
981 void print_value_on_impl(outputStream* st) const;
982
983 #if defined(SUPPORT_DATA_STRUCTS)
984 // print output in opt build for disassembler library
985 void print_relocations_on(outputStream* st) PRODUCT_RETURN;
986 void print_pcs_on(outputStream* st);
987 void print_scopes() { print_scopes_on(tty); }
988 void print_scopes_on(outputStream* st) PRODUCT_RETURN;
989 void print_handler_table();
990 void print_nul_chk_table();
991 void print_recorded_oop(int log_n, int index);
992 void print_recorded_oops();
993 void print_recorded_metadata();
994
995 void print_oops(outputStream* st); // oops from the underlying CodeBlob.
996 void print_metadata(outputStream* st); // metadata in metadata pool.
997 #else
998 void print_pcs_on(outputStream* st) { return; }
999 #endif
1000
1001 void print_calls(outputStream* st) PRODUCT_RETURN;
1002 static void print_statistics() PRODUCT_RETURN;
1003
1004 void maybe_print_nmethod(const DirectiveSet* directive);
1005 void print_nmethod(bool print_code);
1006
1007 void print_on_with_msg(outputStream* st, const char* msg) const;
1008
1009 // Logging
1010 void log_identity(xmlStream* log) const;
1011 void log_new_nmethod() const;
1012 void log_state_change(const char* reason) const;
1013
1014 // Prints block-level comments, including nmethod specific block labels:
1015 void print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels=true) const;
1016 const char* nmethod_section_label(address pos) const;
1017
1018 // returns whether this nmethod has code comments.
1019 bool has_code_comment(address begin, address end);
1020 // Prints a comment for one native instruction (reloc info, pc desc)
1021 void print_code_comment_on(outputStream* st, int column, address begin, address end);
1022
1023 // tells if this compiled method is dependent on the given changes,
1024 // and the changes have invalidated it
1025 bool check_dependency_on(DepChange& changes);
1026
1027 // Fast breakpoint support. Tells if this compiled method is
1028 // dependent on the given method. Returns true if this nmethod
1029 // corresponds to the given method as well.
1030 bool is_dependent_on_method(Method* dependee);
1031
1032 // JVMTI's GetLocalInstance() support
1033 ByteSize native_receiver_sp_offset() {
1034 assert(is_native_method(), "sanity");
1035 return _native_receiver_sp_offset;
1036 }
1037 ByteSize native_basic_lock_sp_offset() {
1038 assert(is_native_method(), "sanity");
1039 return _native_basic_lock_sp_offset;
1040 }
1041
1042 // support for code generation
1043 static ByteSize osr_entry_point_offset() { return byte_offset_of(nmethod, _osr_entry_point); }
1044 static ByteSize state_offset() { return byte_offset_of(nmethod, _state); }
1045
1046 void metadata_do(MetadataClosure* f);
1047
1048 address call_instruction_address(address pc) const;
1049
1050 void make_deoptimized();
1051 void finalize_relocations();
1052
1053 void prepare_for_archiving_impl();
1054
1055 class Vptr : public CodeBlob::Vptr {
1056 void print_on(const CodeBlob* instance, outputStream* st) const override {
1057 ttyLocker ttyl;
1058 instance->as_nmethod()->print_on_impl(st);
1059 }
1060 void print_value_on(const CodeBlob* instance, outputStream* st) const override {
1061 instance->as_nmethod()->print_value_on_impl(st);
1062 }
1063 void prepare_for_archiving(CodeBlob* instance) const override {
1064 ((nmethod*)instance)->prepare_for_archiving_impl();
1065 };
1066 };
1067
1068 static const Vptr _vpntr;
1069 };
1070
1071 #endif // SHARE_CODE_NMETHOD_HPP